[Mere reference to background art herein should not be construed as an admission that such art constitutes common general knowledge in relation to the invention.]
Since the adoption of electricity, in particular distributed electricity, buildings and houses have been fitted with electrical sockets in which electrical plugs, with pins thereon, can electrically engage with. The electrical socket typically has a switch and provides a point at which appliances and devices and the like can be plugged in to. Typically the socket is ‘female’ and the plug with pins is ‘male, with the pins at least comprising a portion of an electrically conductive material (e.g. a suitable metal).
Over time, sockets, in particular wall sockets, developed, some including various features, usually safety features. Different countries and regions developed different power systems and standards, and also different plug/socket combinations. As far as the plug/socket is concerned, the primary differences are most notable in the pin number (e.g. 2 or 3 pins), shape, and configuration. For example, some countries have plugs with generally flat parallel pins, some with angled pins, some with rounded pins, some with square pins, etc.
The differences in pin number, shape, and configuration makes travelling and moving from one type of plug/socket arrangement to another troublesome. This is because electrical appliances/devices are typically shipped with a single pin arrangement suitable for use in the particular country/region that it is sold. When a person travels or moves from that country/region to one with a different type of plug/socket arrangement, the plugs of their appliances/devices will not fit in to the different shaped sockets.
Some pin configurations are similar, and a simple ‘bending’ of the pins may allow a plug of one type to fit into another. For example, a plug with generally flat parallel pins may be bent to be at the appropriate angle for insertion into a socket with angled pins. However, the bent pins typically do not make a very secure electrical engagement with the electrical contacts in the socket, which may mean that electricity is either poorly transferred, not transferred, or that arcing may occur (e.g. if there is an air gap between the pin and the contact). Furthermore, because the pins are bent the plug will likely not fit completely into the socket meaning that portions of the pins where the bend is effected (e.g. twisted) will be exposed. This is an electrocution hazard for anyone near the plug, or could also be a fire or short circuit hazard. Additionally, the bending of the pins may damage the pins, particularly if they are bent too many times.
Another option for allowing a plug of one pin configuration to fit into a socket of another, is to fit another plug with the correct pin configuration. Although this may provide a safe and secure engagement with the socket, disadvantageously this is a more permanent solution and it is not feasible to easily switch between different pin configurations such as, for example, when a person is travelling between many different countries/regions with different plug types.
To more easily facilitate the connection of one plug type in to another socket type, pin adapters have been developed. In one form, a pin adapter has a socket that is suitable for connecting the users plug type in to, and has pins that suit a different socket type. However, to allow for connection of the plug to many different socket types, many different adapters are required (i.e. one adapter for each socket type). Furthermore, the adapter of this form can only receive one plug type, and cannot facilitate the connection of different plug types into any given socket.
To overcome this latter mentioned disadvantage of adaptors, some ‘universal’ adapter with sockets that could receive multiple plug types with different pin configurations were developed. The sockets were shaped to allow a variety of different pin shapes and configurations therein, and to electrically engage with the pins of each configuration. To allow the variety of pin configurations to electrically connect within the socket, the contacts were typically shaped such that they could be engaged with small pins, and also be bendable so that they could be ‘pushed out’ upon insertion of some of the larger pin types. However, when larger pin types were inserted, particularly if inserted a number of times, the pins would bend back. As the contacts bent back more permanently, they no longer provided a suitable safe electrical engagement with the smaller pin types. Particularly, after the contacts had been bent back the smaller pin types would not electrically connect properly and, for example, may intermittently come in and out of electrical engagement. This is not only prone to arcing, which can cause fires or the like, but also can produce electromagnetic interference. Furthermore, if the plug is not engaged securely, the plug may wobble or, worse, fall out of the socket.
Due to these shortcomings, sockets that allow multiple types of plug therein are generally not accepted for everyday or industrial use. Accordingly, even in areas where it would be highly desirable to allow multiple plug types to be connected, for example in an airport or hotel, the universal sockets are generally not considered safe (e.g. don't meet the requisite electrical standards), and therefore only sockets of the particular country/region are utilised and it is up to the user of different plug types to provide their own, possibly unsafe, adapter to interface between their plug type and the socket of another.
It is an aim of this invention to provide an improved power socket which overcomes or ameliorates one or more of the disadvantages or problems described above, or which at least provides a useful alternative.